Oxygen release compound as a chemical treatment for nutrient rich estuary sediments and water

The objectives of this work were: (i) to evaluate the efficacy of Oxygen Release Compound (ORC), oxygen providing agent that enhance the oxidation of organic matter in fresh water, marine water, and sediment; and (ii) to explore the potential aquatic toxicity that might be generated due to its use. A bench scale laboratory experiments were conducted using five different water sources (2 freshwater, 2 marine water and a deionised water). During the assay, flasks of 1 L capacity were dosed with artificial sediment and ORC and kept at room temperature for 10 days. Temperature, pH, DO, UV254, TOC and Mg were periodically measured. The potential aquatic toxicity that might be generated as a by-product of ORC use was performed. The experimental results reveal that ORC is indeed effective in releasing oxygen over a long period of time and it is also effective for the remediation of natural waters enriched with organic matter. The toxicity test shows that ORC treatment did not create any biological toxicity in freshwater samples (IC50<1 Toxicity Unit-TU). However, marine water samples reveal a high toxicity and had IC50>1 TU. The study proves that ORC was an appropriate technology that can safely be used to treat natural waters enriched with nutrient and natural organic matter.